Rotary cutter for making saws.



UNITED STATES CHARLES NAPiER, or SPRINGFIELD, MASSACHUSETTS., ASSiG-oiiffbrlzonh PATENT HALF TO MASSACHUSETTS SAW WORKS, OF CHICOPEE, lllASSACHUSETTSziSfj ROTARY ouTTEr-i 'Fon MAKING sAws.- f

nq. s421903.

This invention relates to vrotary cutters,

1o andhas special reference to a cutter for use in the manufacture ofhack-saws, the object of the invention being to provide a cutter which in its operation on a stack or block of saw-blanks will cut the teeththereon by cutx A ting away the metal at the edge of the blank alternately from-the back and the front edge of the tooth in intersecting lines until the complete tooth of the re uire'd length is formed, a further obj ectof t e invention beeo ing" to' .provide a cutter of this character capable of adjustment whereby on'e cutter may be adjustedfto cut saws having a greater or -less number of .teeth to the inch. The inventionv is fully described in the ane z5`nexed specification and summarized in the lclaims appended thereto, and is fully illustrated in the accompanying drawings, in Which- Figure 1 isa side elevation of a cutter con.

. stack or block of saw-blanks locked in a suit-- able holder, the arbor of the cutter being in section.r Fig. 2 is a front elevation, artly broken away, of the cutter shown in ig, 1 and shows the arrangement of the cutters in interlocking sections on the arbor and the arrangement ofthe cutter-teeth with every Yalternate row in alinement. Fig. 3 is a saw- 4'o blank inside elevation. Fig. 4 is a sawblank in whicha cut has been-made by one row of cuttervteeth forming the beginning of every second tooth in theI saw. Fig. v5 is -a v rsaw-.blankin whichA a cut has been made 4 5 therein between the teeth shown in Fig. 4 'by therow of cutter-teeth following that which .made the cuts shown in Fig. 4. Fig. 6 is .an end .elevation of a cutter having rows of teeth on separate bars adjustable lengthwise 5o ofthe arbor, the latter being in section. Fig. 7is aside elevation ofthe same, a part of the arbor being in section to more clearly show` the` adjusting vdevice for eaehrtoothed bar.

Fig.8` is an end elevation of the arborshown Specification of Letters Patent. .Application tied January 5, 1906. serai No. 294.784.

in Eig.' 7 and Showingurhebben@bf adjusting devices for the toothed bars.` ,t lFi g..,`f9

is a saw-blank in whichfthe toothed'bar hasf made a cut, and Fig. l'slhowsthesame third of the distance between the cut'softhe blank .in Fig. 9. Fig. 1 1 shows a blank in which' another cut has been made bythe third ,baif' of the series Vlocated at two-,thirds of thedislhaving received anothe'rfcut loeatedlat..

tance between two of the cuts *il blankshowninFig. 9. y Thus in this grouping v'of cutterlbarseveryl fourth bar will have its teeth inialinenient,

vthe intermediate, bars'f being oifsetin lthe.

s ame direction to locate theteeth thereof in position to cut as many teethfas desired' bei tween the cuts made by theteethof thefirst bar and to space them equally. t Inthismanner all ofthe, teeth are yformed bysucc'cssiye a, cuts applied to first. one, side of.y the teeth and then to the other in intersectingflines,"the cutters being fedy transversely of as block'fof blanks, or vice versa, operatingkthereonf..to

gradually cut the saw-teethlto the .fulldepth required, the blanks being blockedl andsecured in suitable holders in a mannerto have the teeth oii one saw supportedby` those .of the saws beneath it, and theseteeth'mayfthus be finished at one operation with'` no 'dipl of the points thereof in the direction of the rotation .of the cutters. t. vThis method ofciitting the `saw-teeth is inmarked contrast the method commonly employed whereby the teeth are made by punching out lthe metal.' 4 on the edge of the blank Vto form the teeth and in Whlch there ismore or.lessriragofthel metal, which results in the formationof a bur on the edges of the toothand also ina more or less pronounced deflection ofthe point, as well as a relatively badlyiinished dull point, as dies cannot be,v keptgsharpl enough to cut the apex ofthe "\lproperly,I` The cutter shown in Figs; Land 2v is made up, preferably, of thefV cutterfsections a,

mounted on an arbor b andkeyedthereomas.

by a key c, Fig. 1. These cutter-sections c are also provided Withfp'rojections' .011 the.,

side thereof which interlock withsimilarproi` jections on the side of'thecontiguous cutter,

whereby all the sections on the arbor will ro-. tate as' one and whereby the teethjoneach Section will be alined-With those on the `neig-ty section and the spacing ofthe last tooth n one section and the r'st .toothonfthe e the same as that of the teeth located on the same section. On each of the cutter-sections (it will be seen by reference to Fig. 2) there are alternate rows of `cutter-teeth e andf, which are offset to the extent of one-half the distance between two of these teeth. It is therefore essential that when the sections a. are mounted on the arbor the separate rows of teeth e and f shall be located in the same line longitudinally. This longitudinal alinement of the different rows of the cutter-teeth of one section relative to the next is accurately effected by means of the key c.

Fig. 3 shows a saw-blank g and Fig. 4 shows the same blank after one cut has been made therein, as by the row of teeth indicated byf, with the exception, of course, that in practicev the cutter is of sufficient length to take in the entire saw. The depth of the cut of the notches h in thev blank shown in. Fig. 4 is very much exaggerated, as in practice the first cut would only be a fraction of the depth shown; but it illustrates the principle of` op-i eration of this cutter by showing thatthe various rows of teeth f, for example, on the cutter operate to cut the front of the first tooth and the back ol the one next to it and then skipsthe front and back of the second tooth, cutting the third in the same manner as the first, then the fifth, seventh, and so on. Then when the next row of cutter-teeth c comes in contact with the blank its teeth being located in an offset position, as described, mid.- way between the points of the teeth f, said teeth e will cut the: front and back of the second, fourth, land sixth tooth precisely in the same manner that the teeth f cut the first, third, `fifth,`&c.,- this second operation bythe cutters -e ,resulting in the formation of regularly-spaced teeth j, .as shown in Fig. 5, it beingb'orne in mind, however, that before the full depth of the'teeth is reached, as shown in this last/-named figure, a number of cuts bythe alternate lrows of teeth e and f will havebeen made, one row shaving the metal from the 'front and. the other row shaving offy the metal from the back of a tooth until by successive operations of these cutters in intersecting lines the completed tooth is formed. vBy thus locating the cutter-teeth a comparatively light cutis taken by each row alternately, whereby the cut may be cleanly made through the metal without any of the drag so noticeable when the teeth are formed by punching out a tooth to its full depth at one operation. This improved method results inthe formation of a toothwith a sharp point', which point will lie in the plane of the body 4of the blank instead of to oneJ side thereof, and'incidentally,therefore, 1t also.

results ina tooth having a square point or cutting edge-that is to say, one whose cutting edge will be located practically at right .angles to the plane of the blank.

n properly support the saw-blanks durmg the tooth-forming operation, they are rassembled, as shown in Fig. l, in a suitable holder or clamping device 7c in the form of a llock, the cutter or the holder being movable one relative to the other in a direction at right angles to the axis of the cutters, as in any milling operation.

In the manufacture 'of hack-saws vthe number of ,teeth to the inch varies according to the class of work which they are to perform. Therefore if the cutters were constructed as shown in Figsil and 2 it would be necessary to have as m'any separate lsets of cutters as might be required by the variations in the number of teet'lir to the inch in the dierent, grades of saws. This would entail a very large expense, as a large number of cutters for each grade of saw are required. To obviate this expense, I construct a cutter having adjustable teeth, which construction is;F illustrated in Figs. 6, 7, and 8. In constructing this cutter I form the arbor b in the usual manner except that on one end thereof is a circular heador flange m, a channel o separati the' latter from the end of the arbor.

Longitudinally ofthe latter parallel grooves are cut, having undercut sides to receive the bars p, on the outer edge of which the cutterteeth g are cut, these teeth being equally spaced on all of they bars. Through the flange or head m is an adjusting-screw r,

threaded into the head and enterin the end of each of the barsp, with which it asa rotative engagement, whereby by turning the screw in or out the bar may be movedend/-f wise in its groove. On the screws P are suitable locking-nuts s, which may be set up against the flange to look the screws r in the` r adjusted osition. If now it is desired by the use of) this cutter to form teeth having the spacing shown in Figs. 4 and 5, the bars p would be adjusted in such manner that the teeth g on one of the bars should have their points located midway between thel points of the teeth on the bars both in front and behind it. If, however, it is desired to make two outs instead of one' between the notches h, asshown in Fig. 4, then one bar would be left in its normal position, whereby these cuts being shown clearly in Figs. 9, 10, and

111. a It is thus clear th at for tlis 'purpose the bars' p would be arranged in series'of three', the teeth of'every first and fourth and second and fifth and third and sixth bars having the same planes of. rotation. This construction obviously also requires that the numberof bars shall be such as to permit the subdivision thereof into groups, as described, although if the total number of bars on the arbor were such that they would not divide IOO IIO

equally into groups of three no harm would be do-ne either in having two consecutive bars in alinement circumferentially or by disengaging the adjusting-screw Jfrom 'one bar and withdrawing it completely. How'- ever, it is easy to construct a cutter h'aving a proper number of bars to make the required subdivision into groups.

The .adjusting-screws r are shown merely as a convenient means to move the' bars p, as described; but other adjusting devices having the same function may be substituted y therefor7 if desired.

Having thus described my invention, what I claim, and desire to secure by Letters Patento the United States, is p. 1. A rotary cutter for saws and the like comprising a cylindrical body having on the surface thereof separate longitudinally-arranged rows of continuously formed V- shaped teeth of uniform depth and projection, the teeth in one or4 more rows being offset relative to the-teeth in another .preceding row to locate said offset teeth in planes of rotation which will subdivide' the spaces between the teeth in said preceding row into equal parts.

2. A rotary cutter for saws and -the like comprising separate longitudinallyfdisposed rows of teeth, and means to adjust` said rows endwise to locate the teeth on oneor more of the rows in planes of rotation which will subdivide the space between two teeth in `a preceding row into equal p rts. g

3. A rotary 'cutter for saws and thei like comprising an arbor having langegat one end thereof; separate;` .'lohgitudinallydis- Y posed rows of teeth,endwise movable in the arbor; ascrew extending through the flange and having a rotative engagement withsaid endwise-movable rows of teeth to adjust the latter, one row relative to the other.

CHARLES NAPIER. Witnesses WM, H. CHAPIN, 'y K. I. CLEMoNs. 

